bump garden-integration-tests
bump garden-integration-tests

[finishes #174096808]

Submodule src/garden-integration-tests 7216fd92..a0ce4580:
  > Supplementary groups are not set in rootless

Signed-off-by: Giuseppe Capizzi <1968455d84ef56ceb93e8ec69a3034a6fe0ab9cc@pivotal.io>

cloudfoundry-incubator/guardian-release,cloudfoundry-incubator/guardian-release,cloudfoundry-incubator/guardian-release